Note 8 - Leases (Details Textual) - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended
Nov. 30, 2017	Mar. 31, 2019	Dec. 31, 2018
Sale Leaseback Transaction, Monthly Rental Payments		$ 51,000	$ 16
Finance Lease, Liability, Total		8,000
Finance Lease, Right-of-Use Asset		7,000
Selling, General and Administrative Expenses [Member]
Operating Leases, Rent Expense, Net, Total		400,000	1,200,000
Sale Leaseback Transaction to Sell Tualatin Headquarters And Warehouse [Member]
Sale Leaseback Transaction, Net Proceeds, Investing Activities, Total			8,100,000
Sale Leaseback Transaction, Cumulative Gain Recognized			2,900,000
Sale Leaseback Transaction, Monthly Rental Payments			$ 53,000
Lessor, Operating Lease, Renewal Term			5 years
Vehicles, Equipment, and On Accommodations for Vesting Personnel [Member] \| Energy Segment [Member] \| Orbital UK Reporting Unit [Member]
Operating Leases, Monthly Rent		$ 31,000	$ 32,000
Office and Warehouse Space in Houston [Member]
Lessor, Operating Lease, Renewal Term		5 years
Operating Leases, Monthly Rent	$ 10,000	$ 30,000
Lease Related to Toronto Facility [Member]
Lessor, Operating Lease, Renewal Term		5 years
Operating Leases, Monthly Rent		$ 33,000	34,000
Lease Related to Japan Leases Office Space [Member]
Operating Leases, Monthly Rent		$ 3,000	$ 3,000
Lease Related to Relocated to Another Rented Office and Warehouse [Member]
Operating Leases, Monthly Rent	$ 30,000

The monthly rent expense for an operating lease.

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

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Amount of lessee's right to use underlying asset under finance lease.

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Term of lessor's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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Cumulative amount of gain recognized (out of deferred gain) as income or a reduction in rent expense.

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The amount of the monthly rental payments due under the lease entered into in connection with the transactions involving the sale of property to another party and the lease of the property back to the seller.

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Amount of cash inflow after closing and debt issuance costs received by a seller-lessee in a sale-leaseback recognized in investing activities.

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